♪ Gulnaz Khan: We're in Chinguetti, Mauritania, the gateway to the Sahara in West Africa.

[Wind gusting] ♪ The sand, it turns to dust in your hands, but don't be fooled.

This is one of the most powerful forces on Earth.

You can be standing on a sand dune here and an entire city is frozen in time beneath your feet.

This desert has swallowed entire cities, and now it's on Chinguetti's doorstep.

[Wind gusting] ♪ ♪ [Woman vocalizing] ♪ I am Gulnaz Khan.

As a journalist, I'm reporting on how climate change is endangering humanity's most sacred sites and traditions as well as how faith-based communities around the globe are tackling this humanitarian and existential crisis with innovative solutions.

♪ [Wind blowing] ♪ Khan: The Sahel is a vast, semi-arid region stretching over 3,000 miles from the Atlantic Ocean to the Red Sea.

It's a vital buffer zone between the rapidly expanding Sahara and the fertile lands to the south, protecting one of the world's fastest growing populations from the devastation of desertification.

It's a challenge that has shaped human existence in the region for millennia.

Today, in places like Chinguetti, it's a struggle that's intensifying.

[Man speaking French] ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ Gulnaz: Throughout the Middle Ages, the city was a stopover for pilgrims traveling over land to Mecca, Islam's holiest city.

Over centuries of cultural exchange, its libraries became one of the most important repositories of Islamic knowledge in the world.

[Seif speaking French] ♪ ♪ ♪ ♪ [Camera clicks] ♪ Gulnaz: Chinguetti is considered a sacred site in Islam, but it's so much more than that.

It's world heritage.

It is the cultural heritage of humanity.

This legacy, this treasure trove that's hundreds of years old, science, math, it's being lost by desertification, by rising temperatures, more extreme weather.

[Camera clicks] The Sahel is uniquely vulnerable to climate change.

It's heating up one and a half times faster than the global average, and intensifying an already extreme environment.

♪ [Man speaking French] [Praying] ♪ [Mohamed speaking French] ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ Gulnaz: The original Chinguetti is entirely buried beneath the sand.

So when sand started to creep on the original city, they moved Chinguetti.

There's now another Chinguetti, because this Chinguetti is once again being overtaken by the sands.

And what they're seeing in the newly built version of the city is the sands are creeping up there too.

You know, the locals here, they say the sand always wins.

♪ [Mohamed speaking French] ♪ ♪ When you were growing up, what was it like around here?

[Speaking French] [Door closes] ♪ [Speaks French] ♪ [Speaking French] Wow.

Ha ha ha!

[Mohamed speaking French] How does it make you feel to see it now?

[Speaking French] ♪ Gulnaz: More than 65% of Mauritania's population relies on agriculture and pastoralism.

But worsening periods of drought threaten even the most resilient species, including vital tree populations.

♪ 50 miles from Chinguetti, one oasis lost nearly 20,000 trees in less than 50 years.

♪ As-salamu alaykum.

As-salamu.

Enchante.

♪ So your family has lived in Chinguetti for generations.

So since you were young, how has climate change affected the city and your daily life here?

[Speaking French] Shh... Gulnaz: Why do you think the conservation of the libraries needs to start with environmental conservation?

[Speaking French] [Bleats] [Seif speaking French] Gulnaz: As-salamu alaykum.

Gulnaz, voice-over: We often think of the desert as an absence of life, but it's actually teaming with it.

Hundreds of years of stories of human creativity and innovation are contained within Chinguetti's sands.

But its survival, its resilience, is directly tied to the health of the planet.

Just beyond Chinguetti's borders and across the massive expanse of the Sahara, nomads have lived and thrived in these harsh conditions for millennia, despite receiving less than four inches of rain per year.

But today, they find themselves on the front lines of the climate crisis, where less rain means the difference between life and extreme hardship.

As conditions become more challenging, many nomads have already migrated to cities to live sedentary lifestyles, and an age-old way of life is disappearing.

[Man speaking Hassaniya] [Water splashing] ♪ ♪ [Goats bleating] [Sidi speaks Hassaniya] ♪ [Woman singing in Arabic] ♪ Gulnaz: Trees are vital to saving Chinguetti.

Their roots essentially halt desertification, and we've seen that even the smallest shrubs that you see around the desert here are helping slow the dunes from moving into the city.

So it is absolutely vital that there is regreening here.

♪ The thing that keeps people in Chinguetti is their love of what the place represents, the libraries, the books, the knowledge.

It is essentially the glue that holds the city together.

So many cities like Chinguetti in the desert have been abandoned, they're empty now.

Because life has gotten so much more challenging with climate change, people are actually migrating out of these small villages and towns in the desert into the big cities.

♪ In 1960, Nouakchott, the capital of Mauritania was designed for a population of 15,000.

Since then, desertification has driven more than a third of the country to the shores of the Atlantic Ocean.

And today, it's home to 1.5 million people, straining the city's resources and creating dire humanitarian conditions.

In the last century, the Sahara has expanded more than 10%, and it's now encroaching into the Sahel, the semi-arid belt that spans the continent of Africa.

Here, climate extremes are driving conflict, famine, migration, and ecosystem collapse.

But communities across the region are mobilizing and using traditional knowledge to slow the advance of the desert.

♪ In neighboring Senegal, the Mauritanian desert has already started to bleed across borders.

♪ But in rural areas like Kaffrine, imams and priests are leading an interfaith green revolution.

In recent years, FMNR, or Farmer Managed Natural Regeneration, has emerged as a scalable solution.

In the local language, it's known as RNA, or Carcaral, which literally means "To Stop the Desert."

Anna Daba Ndiaye is a regreening project leader with World Vision.

[Anna speaking Wolof] [Anna speaking French] [Speaking French] Gulnaz: I think at first it might seem odd for an imam and pastor to be learning about farming techniques.

But when they talk about the scripture, about conservation in both the Quran and the Bible, about our responsibility as humans to be stewards of the environment, it makes so much sense, and you wonder why it isn't happening everywhere.

♪ [Anna speaking French] Anna: Voila.

[Speaking French] ♪ ♪ ♪ ♪ ♪ ♪ Gulnaz: FMNR seems like a simple solution to a complex problem, but it works.

Nature is incredibly resilient and it has the ability to heal itself.

Often it's these simple techniques that yields the best results.

♪ ♪ [Fatou speaking Wolof] ♪ ♪ [Indistinct chatter] [Fatou speaking Wolof] Gulnaz, voice-over: Fatou started doing FMNR several years ago in her fields, and that took her crop yields from less than a dollar a day to more than $3.50, which is a staggering increase.

She's also trained more than a dozen other women in Mbane in this technique.

So she hasn't just uplifted her own household, she's uplifting the entire community.

♪ [Speaking Wolof] ♪ ♪ ♪ ♪ ♪ Gulnaz, voice-over: Fatou is a force that could move mountains.

She's an amazing woman who is empowering other women.

She's really incredible.

♪ [Fatou speaking Wolof] ♪ ♪ Gulnaz: Fatou is spreading this technique among her own community, and that's really how these types of solutions work.

They spread by word of mouth, by imams and pastors in their mosques and churches, and it's actually much more effective than these big top-down solutions that come in from big NGOs that don't really understand the local context.

And the amazing thing about FMNR is it is highly adaptable.

So Fatou can do it on her farm in Senegal, and a farmer in Ethiopia can also do it on their land.

[Fatou speaking Wolof] [Pastor chanting] [Chanting continues] Gulnaz: Faith and religion are complicated things.

I think it's undeniable, tragic things have been done in the name of religion, and we can't ignore that.

But it also has immense beauty and power when used for good.

You know, a majority of the world's population belongs to one of the world's major religions.

That's an immense community, and religions have played major roles in other social movements, and I think they have a place here.

They absolutely have a place in fighting the climate crisis.

[Pastors chanting] Gulnaz: FMNR is directly contributing to environmental justice across the Sahel.

Remarkably, over the past two decades, it spread from predominantly Muslim countries in West Africa to Christian communities in the East who are grappling with similar climate challenges.

♪ Ethiopian Orthodox Church forests, cultivated over centuries, are a time capsule of the country's last remaining native biodiversity.

FMNR may be the key to preserving them and regreening the wider landscape.

♪ Man: According to the teaching of the Ethiopian Orthodox Church, every church should have a forest, because the church in the Earth should resemble to the Garden of Eden.

♪ My name is Alemayehu Wassie.

I am a forest ecologist, and I have been doing research and conservation activities for the last 20 years.

♪ When I go to the forest, old forest of Church, it reminds me my childhood, that my mother and father, elders taught me, "This is where God lives.

This is where you get the most blessing."

And then I built upon it my ecological understanding how these forest are really precious, how they're very much important.

It's not only my profession here for me.

It's a kind of emotion.

It's kind of spiritual commitment.

♪ The impact of the climate change is very much visible in Ethiopia, especially in the highland.

♪ For a hundred years almost, 40% of the land mass used to be covered by high forest, but nowadays, we have left only 4%.

♪ So the highland is now, you see, devoid of any green vegetation, but you see dots here and there, and you see a building in the middle that is a church, but enveloped by the forest, which once used to be one part of continuous forest, now fragmented.

♪ OK, let's see what we have here.

I graduated from university in forestry, and my major junior task was, you know, creating forest development.

So to do that, you need some kind of seed source, you know, where should I get native tree seeds?

And I look around, I said, "Wait a minute.

"The seed we have, the leftover we have is around church."

This must be very amazing, and we have to really look at them very seriously.

♪ These forests have been existed for centuries because of the patronage and the commitment of the Ethiopian church, monasteries and fathers.

But because of the population growth and agricultural expansion, these forests are under threat.

♪ Ethiopian Orthodox Church are the last opportunity for Ethiopian biodiversity.

This is a critical time, so we have to protect them.

♪ Gulnaz: Protecting the Church forests isn't just a sacred duty, but a humanitarian one.

70% of the Ethiopian population depends on rain-fed agriculture, but periods of extreme drought and flooding are on the rise as the climate crisis worsens.

Creating a more resilient agricultural system begins with reforestation, which can reduce soil erosion, improve water management, and attract pollinators.

[Man chanting] [Chanting continues] [Man speaks Amharic] [Chanting continues] [Abba speaking Amharic] [Singing in Amharic] ♪ [Abba speaking Amharic] ♪ Alemayehu: Well, after all, the priest and the monks are the guardians who brought these forests to the present time.

But they didn't actually observe the ecological degradation.

So what we do is, we show some scientific data that these forests, although they look intact, but through time, they're degrading.

♪ [Abba speaking Amharic] ♪ Alemayehu: So, the most urgent thing is we have to make the so-called conservation wall.

We call them conservation wall because we make out of rocks and stones collected from the area, they create a barrier for the livestock.

As a result, we have seen after a couple of years, more regeneration, more seedling, more health to the forest.

So it's really working.

There is an opportunity that we can restore back the Ethiopian landscape.

♪ [Alemayehu speaking Amharic] [Abba speaking Amharic] Gulnaz: What Dr. Alemayehu is doing now and working with faith leaders to do is to start expanding that initiative beyond just the churches.

And part of that is using seeds that actually come from the churches because they are the native indigenous species that are super resilient, and the types of trees that should be used in regreening.

♪ [Alemayehu speaking Amharic] [Speaking Amharic] [Speaking Amharic] Alemayehu: FMNR is really the most important thing in landscape restoration.

The church forests, because they were part of one continuous forest, we have to connect these forests through biological corridors.

But the in-between land is always owned by farmers.

So without involving them, without empowering them, you know, to regreening, we don't do anywhere.

We don't achieve anywhere.

So we have to create an agroforestry system.

♪ Gulnaz: The relationship between Dr. Alamayehu and Abba is really emblematic of the strength that comes with bringing together science and faith.

I think a lot of people often see those two things at odds with each other, but Dr. Alamayehu said it himself, that studying science only reinforced his faith.

Alemayehu: Nature is a common treasure.

These forests, they are really home for biodiversity, very much important for the global climate change.

So at the end of the day, we all need a green landscape.

One nation cannot be green by itself.

I believe there are wisdoms across Africa we need to explore.

♪ [Seif speaking French] ♪ [Mohamed speaking French] ♪ Gulnaz: Islam promises the Garden of Eden in heaven.

And I think these sacred spaces here on Earth are the closest that humans feel to that.

♪ [Seif speaking French] ♪ Gulnaz: You know, people practice their faith in so many different ways.

There's so many different belief systems.

What I found is that we are much more similar than we are different.

Seif talked about how when he was young, when the wind would blow through the date palms, he would hear them singing, and that everything in creation sings if we know how to listen.

♪ Abba talked about how the leaves and the plants bow in prayer, that all of creation bows in prayer.

And I think we are living through a time of great turmoil in this world, when our differences are separating us, polarizing.

Whether you're looking out at the sand dunes or you're in the beautiful mountain forests of Ethiopia, we feel something, and that's what makes us human.

It's the great, great thing that connects us.

And I think if we focused more on that, we would be doing a much better job at solving the climate crisis.

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